An explosion at a petrochemical plant in eastern Hungary killed one person and injured seven others on Friday, according to Hungarian energy company Mol Group, which owns the facility.

The blast occurred at the plant in Tiszaújváros during a restart following maintenance operations, Prime Minister Péter Magyar said in a social media statement. Seven people suffered burn injuries in the explosion.

Five helicopters were deployed to transport the injured to hospitals in the cities of Miskolc and Debrecen, according to Minister of Economy and Energy István Kapitány. In a social media post, Kapitány reported that a disaster response mobile laboratory detected no concentrations of hazardous materials above threshold limits at the site.

The fire caused by the explosion has been extinguished, a spokesperson for the regional disaster management authority told state news agency MTI. Dávid Dojcsák said cleanup operations were ongoing and emergency units were securing the site.

Both Minister Kapitány and Mol CEO Zsolt Hernádi were traveling to the explosion site, according to Prime Minister Magyar. "We express our sincere condolences to the family of the deceased and wish the injured a speedy recovery," Magyar wrote on Facebook.